When you create a file, you choose the attributes that file will have;
your choices are made on the basis of how the file will be used. A
file's physical characteristics are determined by the parameters you
choose when you create the file with the HPFOPEN/FOPEN intrinsic
or the BUILD command, or when you specify the file with the
FILE command.
Once a file has been created, its physical
characteristics cannot be changed. The file can be renamed or purged,
but the only way to change its physical characteristics is by building
a new file and copying the contents of the old file into the new.
File equations and HPFOPEN/FOPEN calls cannot alter physical
characteristics of an existing file, but they can alter the way the
file is to be used. Other characteristics of the file that you create can
be redefined each time you open the file. Those characteristics are
discussed in later chapters in this manual.
In this chapter, we will address the following questions:
What intrinsics and commands can you use to specify a file's physical characteristics?
What are the physical characteristics that are determined when you create a file?
